CN210983440U - Image capturing device and electronic device using same - Google Patents

Abstract

The utility model provides a get for instance device and use its electronic device gets for instance device and includes base plate, image sensing layer and optical element layer. The image sensing layer is located on the substrate. The optical element layer is positioned on the image sensing layer and comprises a plurality of first micro-structure lenses. The plurality of light channels corresponding to one of the plurality of first micro-structure lenses of the optical element layer and one of the plurality of pixel sensors of the image sensing layer in the vertical direction at least comprise a first light channel and a second light channel from top to bottom, wherein the area of the first light channel is smaller than or equal to the area of the second light channel, the area of the second light channel is smaller than the sensing area of the pixel sensor, and the sensing area of the pixel sensor is smaller than the projection area of the first micro-structure lens.

Description

Image pickup device and electronic device using the same

technical field

The utility model relates to an imaging device for acquiring biometric images, in particular to an imaging device that can be arranged under a cover plate (for example, a display panel, a touch panel or a finger pressure plate), and an imaging device using the imaging device An electronic device with a biometric identification function.

Background technique

Fingerprint identification devices are divided into capacitive and optical types. Capacitive fingerprint identification devices mainly record fingerprint characteristics through the capacitance changes of multiple touch points, while optical fingerprint identification devices directly acquire fingerprint images to record fingerprints. feature. Capacitive fingerprint identification devices are susceptible to moisture or other electronic noises, resulting in misjudgment problems. Furthermore, if an electronic device (such as a smart phone or a tablet) using a capacitive fingerprint identification device is attached with a protective sticker or a tempered glass or the like, the capacitive fingerprint identification device may not be able to identify a fingerprint.

Although the optical fingerprint identification device can solve the technical problem that the fingerprint cannot be identified due to the attachment of protective stickers or tempered glass, the imaging device in the existing optical fingerprint identification device uses a metal wire to electrically connect the image sensor. If the pixel sensor of the test layer and the circuit or chip on the substrate are not covered and protected by the packaging material, there will be oxidation problems, resulting in poor electrical performance and misjudgment. Furthermore, in order to meet the requirements and trend of miniaturization of electronic devices, the imaging device must also be miniaturized (ie, the volume needs to be smaller and the thickness needs to be thinner), so the imaging device has problems such as poor mechanical strength and easy damage. , resulting in a decline in the product yield of the optical fingerprint identification device.

Please refer to FIG. 1 , which is a schematic diagram of a stack structure of a conventional imaging device. In FIG. 1 , a conventional imaging device 1 for acquiring fingerprint images includes an optical channel layer 11 , an image sensing layer 12 , a substrate 13 and wires 14 , wherein an adhesive layer 152 is formed on the substrate 13 so that the image sensing layer 12 is formed. The adhesive layer 151 is attached to the surface of the substrate 13 and the image sensing layer 12 so that the light channel layer 11 is attached to the surface of the image sensing layer 12 . In addition, the wires 14 are used to electrically connect the pixel sensors of the image sensing layer 12 and the circuits or chips on the substrate 13 to each other. The conventional image capturing device 1 can be connected and fixed with a transparent cover plate by means of pasting, snapping or locking, wherein the cover plate can be a touch panel, a display panel or a finger pressure plate or the like. For example, the conventional imaging device 1 and the cover plate can be connected and fixed by arranging adhesive on the peripheral outer edge of the conventional imaging device 1, or, a frame is used to accommodate the conventional imaging device 1 and the frame is used to make the conventional imaging device 1 The conventional imaging device 1 and the cover plate are engaged or locked with each other. Since the wires 14 are not covered by the encapsulating material, there is the above-mentioned problem of oxidation. Furthermore, when the conventional imaging device 1 is connected and fixed to the cover plate, since the wires 14 and the optical channel layer 11 are not protected, it may also cause The wires 14 and the light channel layer 11 contact the cover plate and are damaged.

In addition, the light channel layer 11 in FIG. 1 may be composed of a plurality of light absorbing materials of high absorption material and light transmitting materials of high light transmission material, and a plurality of light channels are formed between any two adjacent light absorbing materials. , so that the light passes through the optical channel and reaches the pixel sensor of the image sensing layer 12 . In other words, the light channel layer 11 may be a collimator layer. The light channel layer 11 may reduce the irradiation efficiency of light, and even affect the image quality of the fingerprint image. Furthermore, in order to make the light condensing effect better, usually there may be more than one layer of the light channel layer 11 , which also increases the manufacturing cost and component space of the conventional image capturing device 1 , which is not in line with the current miniaturization (light, thin, short) trend.

Utility model content

Based on at least one of the foregoing objectives, an embodiment of the present invention provides an imaging device including a substrate, an image sensing layer and an optical element layer. The image sensing layer is located on the substrate. The optical element layer is located on the image sensing layer, and includes a plurality of first microstructure lenses, and the plurality of first microstructure lenses correspond to a plurality of pixel sensors of the image sensing layer. The optical element layer includes a microstructure layer and an optical channel layer. The microstructured layer includes the plurality of first microstructured lenses. The light channel layer, under the microstructure layer, has a plurality of light channels arranged in multiple layers in an array, wherein one of the plurality of first microstructure lenses and one of the plurality of pixel sensors The plurality of optical channels corresponding to the vertical direction include at least a first optical channel and a second optical channel from top to bottom, wherein the area of the first optical channel is less than or equal to the area of the second optical channel, and the The area of the second light channel is smaller than the sensing area of the pixel sensor, and the sensing area of the pixel sensor is smaller than the projection area of the first microstructure lens.

In an embodiment of the present invention, the thickness of the light channel layer is represented by HC, the thickness of the first microstructure lens is represented by H, and the diameter of the first microstructure lens is represented by WM, and HC≦π((WM/2) ² +H ² )/2H.

In an embodiment of the present invention, HC≤π((WM/2) ² +H ² )/4H.

In an embodiment of the present invention, the optical element layer includes a peripheral protruding structure, the plurality of first microstructure lenses are surrounded by the peripheral protruding structure, wherein the height of the peripheral protruding structure is greater than the plurality of Height of each of the first microstructured lenses.

In an embodiment of the present invention, the peripheral protruding structure is a wall or a second microstructure lens.

In an embodiment of the present invention, the optical element layer includes a filter layer, and the filter layer is located under the light channel layer and above the image sensing layer.

In an embodiment of the present invention, the image pickup device further includes an encapsulation layer, and the encapsulation layer is used to cover the substrate and the image sensing layer, wherein the height of the encapsulation layer is greater than the plurality of first Height of the microstructured lens.

Based on at least one of the foregoing objectives, an embodiment of the present invention provides an imaging device including a substrate, an image sensing layer and an optical element layer. The image sensing layer is located on the substrate. The optical element layer is located on the image sensing layer, and includes a plurality of first microstructure lenses, and the plurality of first microstructure lenses correspond to a plurality of pixel sensors of the image sensing layer. The optical element layer includes a microstructure layer and an optical channel layer. The microstructured layer includes the plurality of first microstructured lenses. The light channel layer, under the microstructure layer, has a plurality of light channels arranged in multiple layers in an array, wherein one of the plurality of first microstructure lenses and one of the plurality of pixel sensors Corresponding to the plurality of light channels in the vertical direction, wherein the thickness of the light channel layer is represented by HC, the thickness of the first microstructure lens is represented by H, and the diameter of the first microstructure lens is represented by WM, and HC≦π((WM/2) ² +H ² )/2H.

In an embodiment of the present invention, HC≤π((WM/2) ² +H ² )/4H.

Based on at least one of the foregoing objectives, an embodiment of the present invention provides an electronic device comprising any of the foregoing imaging devices and a cover plate, wherein the imaging device is disposed under the cover plate.

In short, when the imaging device provided by one embodiment of the present invention is assembled, the first microstructure lens will not be easily damaged, and the imaging device provided by another embodiment of the present invention can obtain better image quality. biometric image.

In order to make the above-mentioned and other objects, features and advantages of the present invention more obvious and easy to understand, a detailed description is made as follows in conjunction with the accompanying drawings.

Description of drawings

FIG. 1 is a schematic diagram of a stack structure of a conventional imaging device.

FIG. 2A is a schematic view of the stack structure of the imaging device according to the first embodiment of the present invention.

FIG. 2B is a schematic view of the stack structure of the imaging device according to the second embodiment of the present invention.

FIG. 3 is a schematic diagram of a stack structure of an imaging device according to a third embodiment of the present invention.

4 is a schematic diagram of a stack structure of an electronic device according to a fourth embodiment of the present invention.

5 is a schematic diagram of a stack structure of an electronic device according to a fifth embodiment of the present invention.

6 is a schematic diagram of a stack structure of an electronic device according to a sixth embodiment of the present invention.

7 is a schematic diagram of a stack structure of an electronic device according to a seventh embodiment of the present invention.

8 is a waveform diagram of an electrical signal generated by a pixel sensor according to a seventh embodiment of the present invention.

FIG. 9 is a schematic plan view of an imaging device according to a seventh embodiment of the present invention.

10 is a schematic diagram of a stack structure of an electronic device according to an eighth embodiment of the present invention.

in:

1: Traditional imaging device 11: Optical channel layer

12: Image sensing layer 13: Substrate

14: Conductor 151: Adhesive layer

152: Adhesive layer 2: Image pickup device

21: Microstructure layer 211: Peripheral protrusion structure

212: first microstructure lens 22: light channel layer

221: Light absorbing material 222: Light channel

23: Filter layer OL: Optical element layer

24: Image sensing layer 241: Pixel sensor

242: Pad 25: Substrate

26: Wire 27: Encapsulation layer

2X: imaging device 27’: encapsulation layer

271: Positioning part 2': Image pickup device

22': Optical Channel Layer 4: Electronics

31: Cover 32: Middle frame

4': Electronics 32': Middle frame

4”: Electronic device OL’: Optical element layer

2": image acquisition device 23': filter layer

4”’: Electronic device OL”: Optical element layer

2”’: Acquisition device 22”: Optical channel layer

222a: first channel 222b: second channel

W1: ruler diameter W2: ruler diameter

WM: ruler diameter WS: ruler diameter

HT: Thickness HC: Thickness

H: Thickness AM: Projected area

9: Electronics 91: Cover

92: Acquisition device 9211: Microstructure layer

9221: Optical Channel Layer 92111: First Microstructure Lens

92212: Optical channel 921n: Microstructure layer

922n: light channel layer 921n1: first microstructure lens

922n2: Optical Channel 923: Image Sensing Layer

9231: Pixel sensor.

Detailed ways

In order to fully understand the purpose, features and effects of the present utility model, the present utility model will be described in detail by the following specific embodiments and the accompanying drawings, as follows.

One of the embodiments of the present invention provides an imaging device for acquiring biometric images, which can be disposed under a cover plate. The optical element layer of the imaging device is provided with a plurality of first microstructure lenses and at least one peripheral protruding structure, wherein at least one peripheral protruding structure surrounds the plurality of first microstructure lenses, and the height of the peripheral protruding structure is greater than that of each first microstructure. The height of the structured lens. Furthermore, the wires for electrically connecting the pixel sensor of the image sensing layer of the imaging device and the circuit or chip on the substrate and part of the substrate are covered by the encapsulation layer. In this way, the above-mentioned structure can solve the technical problems that the wires of the conventional imaging device are easily oxidized, the wires and the bonding pads are poorly bonded, and the optical element layer or the chip is easily damaged by touching the cover plate. In addition, the above-mentioned encapsulation layer may be selectively omitted when the technical problems of easy oxidation of wires and poor bonding between wires and pads are not considered.

Another embodiment of the present invention provides another imaging device for acquiring biometric images, which can be disposed under a cover plate. The optical element layer of the imaging device is provided with a plurality of first microstructure lenses, and the optical element layer also has an optical channel layer disposed under the plurality of first microstructure lenses and above the plurality of pixel sensors. The plurality of light channels are configured corresponding to the plurality of first microstructure lenses and the plurality of pixel sensors, and at least two or more light channels are disposed corresponding to each of the first microstructure lenses and each pixel sensor, For example, the two light channels sequentially descending from a first microstructure lens are respectively the first light channel and the second light channel. By designing the area A1 of the first optical channel, the area A2 of the second optical channel, the sensing area As of the pixel sensor, and the projected area Am of the first microstructure lens, the relationship of "A1≤A2<Am<As" If the formula is established, a biometric image with better image quality can be obtained. On the other hand, through the above-mentioned design method, the image pickup device can be selectively not designed to have a plurality of light channel layers, so as to solve the technical problem that the thickness of the image pickup device is too thick.

In addition, in addition to designing the area A1 of the first optical channel, the area A2 of the second optical channel, the sensing area As of the pixel sensor, and the projected area Am of the first microstructure lens, a biometric image with better image quality can be obtained. Another way can be to design the relationship of thickness, and this method can also solve the technical problem that the thickness of the traditional imaging device is too thick. In the embodiment of the present invention, the design relationship HC≤π((WM/2) ² +H ² )/2H can immediately achieve the above purpose, wherein HC is the thickness of the light channel layer, and H is the first micrometer. The thickness of the structured lens, and WM are the diameter of the first microstructured lens.

Furthermore, another embodiment of the present invention provides an electronic device capable of identifying biological features, which includes any of the above-mentioned imaging devices, the above-mentioned cover plate, and a processing circuit, and the processing circuit is electrically connected to the imaging device for receiving and identifying. The biometric image acquired by the imaging device. The cover plate can be one or a combination of a light-transmitting plate, a finger pressure plate, a display panel, a touch panel, an organic light-emitting display panel, a quantum dot display panel, or a display panel with touch electrodes, and the utility model Not limited. The biometric image is, for example, a fingerprint image, a vein image, a blood oxygen image, a palm print image, a pupil image, an iris image or a blood sugar image, and the present invention is not limited thereto. Please note that the types of the above-mentioned cover plate and biometric image are not intended to limit the present invention. In addition, when the cover plate is a touch panel or a display panel, the touch panel or the display panel can be directly or indirectly joined with the imaging device by its frame. For example, the middle frame can be connected with the imaging device by directly pasting, clamping or locking, or the imaging device can be combined with the clamping member or the locking member and then clamped or locked to the middle frame for engagement. . All in all, the present invention is not limited by the joining manner of the middle frame and the imaging device. For example, the cover plate itself can also be pasted, clamped or locked with the imaging device, instead of being coupled with the imaging device through the middle frame of the cover plate.

First, please refer to FIG. 2A . FIG. 2A is a schematic diagram of the stack structure of the imaging device according to the first embodiment of the present invention. In FIG. 2A , the imaging device 2 includes an optical element layer OL (which includes a microstructure layer 21 , an optical channel layer 22 and a filter layer 23 ), an image sensing layer 24 , a substrate 25 , wires 26 and an encapsulation layer 27 . The image sensing layer 24 is located on the substrate 25 , the optical element layer OL is located on the image sensing layer 24 , and the wires 26 are used to electrically connect the pixel sensors 241 on the image sensing layer 24 and the circuit or circuit on the substrate 26 . The chip, and the encapsulation layer 27 are used to cover portions of the substrate 26 and the wires 26 to thereby protect the wires 26 and/or circuits or chips on the substrate 26 .

The image sensing layer 24 includes a plurality of pixel sensors 241 arranged in an array on the upper surface of the image sensing layer 24 . Furthermore, the image sensing layer 24 further has pads 242 disposed on one side of the upper surface of the image sensing layer 24 , and the pads 242 are electrically connected to the plurality of pixel sensors 241 , wherein the wires 26 are used for electrical connection The pads 242 are connected to the circuit or chip on the substrate 25 . The encapsulation layer 27 covers the wires 26 , the pads 242 , the surrounding portion of the upper surface of the substrate 25 and the side where the pads 242 on the upper surface of the image sensing layer 24 are located. Through the protection of the encapsulation layer 27, technical problems such as easy oxidation of the wires 26 and poor bonding between the wires 26 and the pads 242 can be reduced. Even, because of the protection of the encapsulation layer 27, the circuits and chips on the substrate 25 will not be affected by the image pickup. The device 2 is engaged with the cover, and there is a technical problem of being touched and damaged.

In addition, the filter layer 23 is located on the upper surface of the image sensing layer 24 to cover all the pixel sensors 241 . The filter layer 23 can filter out the light of a specific wavelength, so that the pixel sensor 241 can sense the light of the specific wavelength, so as to obtain a biometric image with better image quality. For example, the filter layer 23 can be far-infrared light, near-infrared light, infrared light, visible light or a filter layer of a specific wavelength, and the present invention does not limit the type of the filter layer 23, the type of the filter layer 23 can be is selected according to the actual application. Furthermore, the position and quantity of the filter layer 23 are not intended to limit the present invention, and the filter layer 23 can be moved to other positions above the image sensing layer 24 according to the needs, and even the filter layer 23 can be is a non-essential component and was removed. In addition, the bonding method between the image sensing layer 24 and the substrate 25 and the filter layer 23 can be accomplished by bonding (for example, through the adhesive layer (not shown in FIG. 2A )), but the present invention does not use this method. for restrictions.

In the first embodiment, although the light source is not shown in FIG. 2A, in fact, the light source can be arranged on the back or side of the imaging device 2 (that is, the light source can be a backlight or a side light source), or, when the cover is For the display panel or the touch display panel, the light source may use the light source of the cover plate or other auxiliary light sources, and further, the light source may be visible light, far infrared light, near infrared light or light sources with other wavelengths. All in all, the present invention does not limit the type of light source. The substrate 25 can be a multi-layer or single-layer, flexible or non-flexible, transparent or non-transparent circuit board depending on its application, and its material can be silicon, acrylic or glass, etc., and the present invention is not limited thereto.

Furthermore, the light channel layer 22 is located on the image sensing layer 24, and the light channel layer 22 can be composed of a light absorption material 221 of a high absorption material and a light transmission material of a high light transmission material (the part other than the light absorption material 221, and The light-transmitting material can be formed in one piece), and the light-absorbing materials 221 are laid in an array to form a black matrix, wherein any two adjacent ones of the plurality of light-absorbing materials 221 are formed with light channels 222 (ie, light channels 222). The channel layer 22 is formed as a collimator layer). The microstructure layer 21 includes a peripheral protruding structure 211 and a plurality of first microstructure lenses 212 (the shape can be hemispherical, but the present invention is not limited to this), wherein the peripheral protruding structure 211 surrounds the plurality of first microstructure lenses 212. Each light channel 222 corresponds to one pixel sensor 241 and one first microstructure lens 212 of the microstructure layer 21 . The light emitted by the light source will be reflected by an object close to the imaging device 2 (for example, a finger, but the present invention is not limited to this), and will pass through the corresponding light channel 222 through the focusing action of the first microstructure lens 212 , to be absorbed by the pixel sensor 241 . The plurality of pixel sensors 241 are used to convert the received light into a plurality of electrical signals, thereby generating biometric images.

In the first embodiment, the height of the peripheral protruding structures 211 is greater than the height of each of the first microstructure lenses 212 , and the height of the peripheral protruding structures 211 is the same as the height of the encapsulation layer 27 . When engaging, the peripheral protruding structure 211 plays a protective role, so that the cover plate will not touch the first microstructure lens 212, and the first microstructure lens 212 will not be damaged. Please note that in the first embodiment, the peripheral protruding structure 211 is a part of the microstructure layer 21 (ie, the first microstructure lens 212 and the peripheral protruding structure 211 are integrally formed), but in other embodiments, the peripheral The protruding structure 211 may be a part of the encapsulation layer 27, and the present invention is not limited thereto. In addition, the height of the encapsulation layer 27 can also be different from the height of the peripheral protruding structures 211 , but higher or lower than the height of the peripheral protruding structures 211 , but preferably greater than the height of the first microstructure lens 212 . Besides, the peripheral protruding structure 211 can be a wall or a second microstructure lens in the first embodiment, and the present invention is not limited thereto.

In addition, please refer to FIG. 2B . FIG. 2B is a schematic diagram of the stack structure of the imaging device according to the second embodiment of the present invention. Unlike the encapsulation layer 27 in the first embodiment of FIG. 2A that is formed last and covers the image sensing layer 24 and the substrate 25 , in the second embodiment, the encapsulation layer 27 ′ of the image pickup device 2X is formed on the optical element layer OL Formed before lamination, the encapsulation layer 27 ′ is located around the image sensing layer 24 to form a positioning portion 271 . The optical element layer OL is fixed on the image sensing layer 24 through the positioning portion 271 of the encapsulation layer 27', and maintains a vertical distance from the image sensing layer 24. In this way, the bonding loss caused by the difference in thermal expansion coefficient between the pixel sensor 241 and the optical element layer OL can be avoided. Furthermore, since the height of the positioning portion 271 can be controlled during formation, the image sensing layer The vertical distance between 24 and the optical element layer OL can thus be adjusted so that the image quality and clarity of the biometric image can be improved.

Next, please refer to FIG. 3 of the present design. FIG. 3 is a schematic view of the stack structure of the imaging device according to the third embodiment of the present invention. Different from the light channel layer 22 of the first embodiment of FIG. 2A , there is only one light channel 222 in the vertical direction corresponding to one pixel sensor 241 and the first microstructure lens 212 (ie, only laid in the light channel layer 22 ) A layer of light absorbing materials 221 arranged in an array. In the third embodiment, the light absorbing materials 221 in the light channel layer 22 ′ of the imaging device 2 ′ are laid in a multi-layer manner (for example, three layers), There are three optical channels 222 in the vertical direction corresponding to one pixel sensor 241 and the first microstructure lens 212, thereby increasing the collimation effect and improving the image quality and clarity of the biometric image. Furthermore, the plurality of optical channels corresponding to the vertical direction can be in the form of tapering, gradual expansion or equal diameter from top to bottom, and the present invention is not limited to this, but the tapered form is obtained. The image quality of the biometric image is better.

In addition, please refer to FIG. 4 , which is a schematic diagram of a stack structure of an electronic device according to a fourth embodiment of the present invention. In the fourth embodiment, the electronic device 4 includes a cover plate 31 and the aforementioned image capturing device 2 in FIG. 2A (the image capturing device 2 can also be replaced by the image capturing devices 2 ′ and 2X in FIGS. 2B and 3 ), wherein the image capturing device 2 The top surface of the encapsulation layer 27 of the device 2 and a part of the top surface of the peripheral protruding structure 211 are attached to the middle frame 32 of the cover plate 31 to form the electronic device 4 . The electronic device 4 can be a smart phone, a tablet computer, a bank ATM or a work machine, etc., and the type of the electronic device 4 is not used to limit the present invention.

In addition, the peripheral protruding structure 211 has a stepped shape in a possible embodiment, and the length of the middle frame 32 can extend to part of the peripheral protruding structure 211 to enhance the fastening with the cover plate 31 . Furthermore, as mentioned above, the present invention is not limited to the connection relationship between the middle frame 32 and the cover plate 31, and other solutions (such as snap-fit or screw-locking) can be implemented in addition to adhesive bonding. ) etc., should be covered by any embodiment of the present invention.

In addition, please refer to FIG. 5 , which is a schematic diagram of a stack structure of an electronic device according to a fifth embodiment of the present invention. Different from the electronic device 4 of the fourth embodiment, the top surface of the encapsulation layer 27 of the imaging device 2 and part of the top surface of the peripheral protruding structure 211 are attached to the middle frame 32 of the cover plate 31 . In the fifth embodiment, The middle frame 32 ′ of the cover plate 31 of the electronic device 4 ′ is only attached to the top surface of the encapsulation layer 27 . In other words, the present invention is not limited by the position and details of the fitting.

Please refer to FIG. 6 , which is a schematic diagram of a stack structure of an electronic device according to a sixth embodiment of the present invention. In the sixth embodiment, the electronic device 4 ″ includes an image capturing device 2 ″ and a cover plate 31 , wherein the filter layer 23 different from the first embodiment is located between the light channel layer 23 and the image sensing layer 24 , and image capturing The filter layer 23' of the optical element layer OL' of the device 2" is located on the encapsulation layer 27 and the peripheral protrusion structure 211 of the light pass layer 22, and the cover plate 31 is directly attached to the filter layer 23'. The area where the optical layer 23 ′ is attached to the cover plate 31 is compared with the area where the middle frame 32 is attached to the peripheral protruding structure 211 and the encapsulation layer 27 in the fourth embodiment. Better bonding force to reduce the probability of the image pickup device 2" being detached from the cover plate 31 or the image pickup device 2" being damaged. Furthermore, as mentioned above, the number of filter layers is not limited. Therefore, in addition to the filter layer 23 ′ disposed on the peripheral protruding structure 211 of the encapsulation layer 27 and the light-pass layer 22 , another filter layer can be disposed. The optical layer is between the image sensing layer 24 and the optical channel layer 23 .

Please refer to FIG. 7 , which is a schematic diagram of a stack structure of an electronic device according to a seventh embodiment of the present invention. In the seventh embodiment, the electronic device 4 ″′ includes an imaging device 2 ″′ and a cover plate 31 , and the cover plate 31 is attached to the imaging device 2 ″′, which is different from the imaging device 2 in the first embodiment. , the light-absorbing material 221 of the array configuration of the optical element layer OL" of the imaging device 2"' has two layers in total, and there are two optical channels in the vertical direction (from top to bottom, called the first optical channel 222a and the second light channel 222b) correspond to one first microstructure lens 212 and one pixel sensor 241.

In the seventh embodiment, since the light channel layer 22 ″ is located between the microstructure layer 21 and the image sensing layer 24 , the crosstalk of light with a large angle can be reduced, thereby improving the image quality of the biometric image. Furthermore, through this design method, the light channel layer 22' can be selectively made unnecessary to be too thick, so that the imaging device 2"' conforms to the trend of miniaturization. The thickness of the channel layer is as high as 130 microns, and the thickness HT of the light channel layer 22" plus the microstructure layer 21 can be reduced to 80 microns.

Please refer to FIG. 7 and FIG. 8 together. FIG. 8 is a waveform diagram of an electrical signal generated by a pixel sensor according to a seventh embodiment of the present invention. When an object (for example, a finger) touches the cover plate, since the finger has a fingerprint pattern, the plurality of electrical signals obtained by the plurality of pixel sensors according to the illuminance of the received light will include the high-amplitude signal shown in FIG. 8 and the low-amplitude signal. The way to evaluate whether the biometric image is recognizable can be measured by the evaluation factor. The formula of the evaluation factor is E=avg(low)/avg(high), where E is the evaluation factor and avg(high) is the average of the high-amplitude signals. value, and avg(low) is the average value of low-amplitude signals. When the evaluation factor is less than or equal to 30%, it means that the biometric image is recognizable; otherwise, it means that the biometric image is unrecognizable.

Next, please refer to FIG. 7 and FIG. 9 . FIG. 9 is a schematic plan view of the imaging device according to the seventh embodiment of the present invention. In the seventh embodiment, in order to make the image quality of the biometric image better, the area A1 of the first light channel 222a, the area A2 of the second light channel 222b, the sensing area As of the pixel sensor 241 and the first The projected area Am of the microstructured lens 212 needs to be designed so that the relationship “A1≤A2<Am<As” is established, wherein the area A1 of the first optical channel 222a and the area A2 of the second optical channel 222b are respectively associated with the first The diameter W1 of the light channel 222a (which may be the diameter or width according to its shape) and the diameter W2 of the second light channel 222b (which may be the diameter or width according to its shape), the projected area Am of the first microstructure lens 212 Corresponding to the size WM of the first micro-structured lens 212 (according to its shape, it may be diameter or width), and the sensing area As of the pixel sensor 241 is related to the size WS of the pixel sensor 241 (according to its shape) , possibly diameter or width). In general, compared with the prior art, in addition to the substantial reduction in thickness of the image capturing device 2"', the illuminance of the light obtained by the pixel sensor 241 is approximately 10 times higher.

In addition, the thickness HC of the light channel layer 22' and the thickness H of the first microstructure lens 212 also affect the image quality of the biometric image (measured by an evaluation factor). Please refer to Table 1. Table 1 lists the evaluation factors under various test cases. From Table 1, we can know that when the relational expression "HC≤π((WM/2) ² +H ² )/2H" is established, there will be It has better image quality, and when the relation of "HC≤π((WM/2) ² +H ² )/4H" is established, the image quality is even better. In short, the purpose of obtaining a biometric image with better image quality and reducing the thickness of the imaging device 2"' can be achieved by designing the above-mentioned relationship between the thickness and/or the area.

Table I

A(μm²) A2(μm²) Am(μm²) As(μm²) WM(μm) H(μm) HC(μm) Evaluation Factor E (%) Is it identifiable Test Example 1 78.5 78.5 490.62 625 25 4.387 30 20.2 Can Test Example 2 78.5 78.5 346.18 625 twenty one 2.98 30 25 Can Test Example 3 314 78.5 346.18 625 twenty one 2.98 40 37.6 no Test Example 4 78.5 153.86 346.18 625 25 4.387 46 29.8 Can Test Example 5 78.5 153.86 113.04 625 25 4.387 30 46.3 no

In the seventh embodiment, as long as the relational expression “A1≤A2<Am<As” can be satisfied, the diameter W1 of the first optical channel 222a and the diameter W2 of the second optical channel 222b can range from 2 μm to 30 μm. microns. The shapes of the projected areas Am of the first light channel 222a, the second light channel 222b and the first microstructure lens 212 may be circular, square or polygonal, and the shapes are not intended to limit the present invention. Furthermore, the cover plate 31 itself or its frame (not shown in FIG. 9 ) can be glued to the encapsulation layer 27 and the peripheral protruding structure 211 in a mouth-shaped manner.

Next, please refer to FIG. 10 , which is a schematic diagram of a stack structure of an electronic device according to an eighth embodiment of the present invention. In the eighth embodiment, the electronic device 9 includes a cover plate 91 and an imaging device 92. The imaging device 92 of the eighth embodiment is substantially the same as the imaging device 2"' of the seventh embodiment, and the difference is only that, The imaging device 92 is provided with a plurality of optical channel layers 9221-922n and a plurality of microstructure layers 9211-921n, wherein from top to bottom, a microstructure layer 9211, an optical channel layer 9221, . . . , a microstructure layer 921n, The optical channel layer 9922n and the image sensing layer 923, so that each pixel sensor 9231 corresponds to n first microstructure lenses 92111, ..., 921n1 and n optical channels 92212, ..., 922n2 in the vertical direction. In the eighth embodiment, any one of the first microstructure lenses 92111, . The peripheral protruding structure is shown, but the image capturing device 92 can also have the aforementioned peripheral protruding structure. In addition, in order to obtain better image quality, the eighth embodiment needs to satisfy the relationship of "A1≤A2≤...≤An<Am<As" formula, where A1 to An are the areas of the optical channels 92212, . . . , 922n2, respectively.

Incidentally, the light channel of the light channel layer in the above-mentioned embodiments is realized by light-absorbing material and light-transmitting material, but the light channel layer can also be formed by arranging optical fibers, collimators, pinholes, and patterned materials. The light channel is realized by forming small holes or gratings. In a word, the present invention is not limited by this. Furthermore, the material of the above-mentioned cover plate can be rigid material or flexible material, for example, glass, polymethyl methacrylate (PMMA) or polycarbonate (PI) or other materials, and the material of the cover plate is usually selected to be suitable for visible light. Materials with transmittance greater than 80%, but the present invention is not limited by the material of the cover plate. In addition, in order to prevent the user from using a forged object with biometric features, the imaging device may further have a temperature sensor or simultaneously acquire different types of biometric images to achieve the purpose of anti-counterfeiting.

To sum up the above, the image pickup device of one embodiment of the present invention uses a package layer and a peripheral protrusion structure to solve the problems of easy oxidation of wires, poor bonding between wires and pads, and easy touch of optical element layers or chips in conventional image pickup devices. The technical problem of damage caused by touching the cover. In addition, the imaging device according to another embodiment of the present invention obtains biological features with better image quality by designing the areas of a plurality of optical channels, the sensing area of the pixel sensor and the projection area of the first microstructure lens Therefore, it can be selectively not designed to have a plurality of light channel layers, so as to solve the technical problems that the thickness of the imaging device is too thick and the image quality is poor.

The present invention has been disclosed above with preferred embodiments, but those skilled in the art should understand that the above embodiments are only used to describe the present invention, and should not be construed as limiting the scope of the present invention. It should be noted that all changes and substitutions equivalent to those of the foregoing embodiments should be set to be included within the scope of the present invention.

Claims (10)

1. An image capturing apparatus, comprising:

a substrate;

an image sensing layer located on the substrate; and

the optical element layer is positioned on the image sensing layer and comprises a plurality of first micro-structure lenses, and the plurality of first micro-structure lenses correspond to the plurality of pixel sensors of the image sensing layer;

wherein the optical element layer comprises:

a microstructure layer including the plurality of first microstructure lenses; and

an optical channel layer, located under the microstructure layer, having multiple optical channels arranged in an array, wherein one of the first micro-structure lenses and one of the pixel sensors correspond to the optical channels in a vertical direction, and the optical channels at least include a first optical channel and a second optical channel from top to bottom, wherein an area of the first optical channel is smaller than or equal to an area of the second optical channel, an area of the second optical channel is smaller than a sensing area of the pixel sensor, and the sensing area of the pixel sensor is smaller than a projection area of the first micro-structure lens.

2. The image capturing device as claimed in claim 1, wherein the thickness of the light channel layer is denoted as HC, the thickness of the first micro-structured lens is denoted as H, and the diameter of the first micro-structured lens is denoted as WM, and HC ≦ π ((WM/2)²+H²)/2H。

3. The image capturing apparatus as claimed in claim 2, wherein HC ≦ π ((WM/2)²+H²)/4H。

4. The image capturing apparatus as claimed in claim 1, wherein the optical element layer includes a peripheral protrusion structure, the first micro-structural lenses are surrounded by the peripheral protrusion structure, and a height of the peripheral protrusion structure is greater than a height of each of the first micro-structural lenses.

5. The image capturing apparatus as claimed in claim 4, wherein the peripheral protrusion structure is a fence or a second micro-structured lens.

6. The image capturing apparatus of claim 1, wherein the optical element layer comprises: and the filter layer is positioned below the optical channel layer and above the image sensing layer.

7. The image capturing apparatus of claim 1, further comprising:

and the packaging layer is used for covering the substrate and the image sensing layer, wherein the height of the packaging layer is greater than that of the first micro-structure lenses.

8. An image capturing apparatus, comprising:

a substrate;

an image sensing layer located on the substrate; and

the optical element layer is positioned on the image sensing layer and comprises a plurality of first micro-structure lenses, and the plurality of first micro-structure lenses correspond to the plurality of pixel sensors of the image sensing layer;

wherein the optical element layer comprises:

a microstructure layer including the plurality of first microstructure lenses; and

a light channel layer under the microstructure layer and having multiple light channels arranged in array, wherein one of the first micro-structure lenses and one of the pixel sensors correspond to the light channels in the vertical direction, the thickness of the light channel layer is represented by HC, the thickness of the first micro-structure lens is represented by H, the size of the first micro-structure lens is represented by WM, and HC is less than or equal to pi ((WM/2))²+H²)/2H。

9. The image capturing apparatus as claimed in claim 8, wherein HC ≦ π ((WM/2)²+H²)/4H。

10. An electronic device, comprising; the image capturing apparatus as claimed in any one of claims 1 to 9; and

a cover plate, wherein the image capturing device is arranged under the cover plate.

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